Mobile device

1. A mobile device that can be charged using an electric power signal received from a wireless power transmitter, the mobile device comprising: a secondary battery; a wireless power receiver that receives the electric power signal; a charger circuit that charges the secondary battery using electric power received by the wireless power receiver; and a sensor that detects whether or not the mobile device has been moved from a charging stand after the wireless power receiver transmits, to the wireless power transmitter, an EPT (End of Power Transfer) packet that indicates that charging of the secondary battery has been completed.

2. The mobile device according to claim 1 , further comprising a notifying unit that notifies a user of the mobile device when the mobile device remains placed on the charging stand after the EPT packet is transmitted.

3. The mobile device according to claim 1 , wherein the sensor comprises a magnetic sensor.

4. The mobile device according to claim 1 , wherein the sensor comprises an acceleration sensor.

5. The mobile device according to claim 1 , wherein the sensor comprises a gyro sensor.

6. The mobile device according to claim 1 , wherein the sensor comprises a touch sensor.

7. The mobile device according to claim 1 , wherein the sensor comprises a touch panel.

8. The mobile device according to claim 1 , wherein the sensor comprises a physical button.

9. The mobile device according to claim 1 , wherein the sensor comprises a camera.

10. The mobile device according to claim 1 , wherein the sensor comprises an illumination sensor.

11. The mobile device according to claim 1 , wherein the sensor detects an electromagnetic field signal that occurs due to an analog ping generated by the wireless power transmitter.

12. The mobile device according to claim 2 , wherein the notifying unit prompts the user of the mobile device to place the mobile device on the charging stand again after detaching the mobile device from the charging stand.

13. The mobile device according to claim 2 , wherein the notifying unit instructs a display apparatus to display a message that prompts the user of the mobile device to place the mobile device on the charging stand again after detaching the mobile device from the charging stand.

14. The mobile device according to claim 2 , wherein the notifying unit outputs a notice in the form of a voice or a sound that the mobile device has been left on the charging stand.

15. The mobile device according to claim 2 , wherein the notifying unit vibrates the mobile device.

16. The mobile device according to claim 2 , wherein the notifying unit notifies the user of the mobile device after a predetermined period of time elapses after the EPT packet is transmitted.

17. The mobile device according to claim 2 , wherein the notifying unit notifies the user of the mobile device when the remaining battery charge becomes smaller than a predetermined threshold value after the EPT packet is transmitted.

18. The mobile device according to claim 1 , that conforms to the Qi standard.

19. A control method for a mobile device that can be charged using an electric power signal received from a wireless power transmitter, the control method comprising: receiving the electric power signal from the wireless power transmitter; charging a secondary battery using the electric power thus received; transmitting an EPT (End of Power Transfer) packet to the wireless power transmitter when charging of the secondary battery has been completed; detecting whether or not the mobile device has been moved from a charging stand after the EPT packet is transmitted; and notifying a user of the mobile device when the mobile device remains on the charging stand after the EPT packet is transmitted.